The 39-year-old was caught during a routine residency inspection at a hotel in Hanoi's Hoan Kiem District on April 25, according to a statement released by Hanoi police's Immigration Management Division on Friday.
Officials said the man had originally entered Vietnam on a valid electronic visa, which was set to expire on March 31, 2025. But instead of leaving the country as required, he allegedly tampered with the expiration date in an attempt to extend his stay unlawfully.
Hanoi police imposed an administrative fine of VND8 million ($307) and ordered his immediate deportation.
Authorities have warned foreign visitors that any tampering with visas or residency documents will not be tolerated and may result in severe penalties, including deportation.
Hotels and guesthouses across Vietnam have also been urged to double-check the immigration documents of foreign guests and report any suspected forgeries to law enforcement without delay.
Vietnam offers 90-day e-visa for all foreign arrivals, except for those from 25 countries who enjoy visa exemption.